Sagi, Yes, Multipath is disabled. This time, with "nvme-fabrics: allow to queue requests for live queues" patch applied, I see hang only at blk_queue_enter(): [Jul28 17:25] INFO: task nvme:21119 blocked for more than 122 seconds. [ +0.000061] Not tainted 5.8.0-rc7ekr+ #2 [ +0.000052] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. [ +0.000059] nvme D14392 21119 2456 0x00004000 [ +0.000059] Call Trace: [ +0.000110] __schedule+0x32b/0x670 [ +0.000108] schedule+0x45/0xb0 [ +0.000107] blk_queue_enter+0x1e9/0x250 [ +0.000109] ? wait_woken+0x70/0x70 [ +0.000110] blk_mq_alloc_request+0x53/0xc0 [ +0.000111] nvme_alloc_request+0x61/0x70 [nvme_core] [ +0.000121] nvme_submit_user_cmd+0x50/0x310 [nvme_core] [ +0.000118] nvme_user_cmd+0x12e/0x1c0 [nvme_core] [ +0.000163] ? _copy_to_user+0x22/0x30 [ +0.000113] blkdev_ioctl+0x100/0x250 [ +0.000115] block_ioctl+0x34/0x40 [ +0.000110] ksys_ioctl+0x82/0xc0 [ +0.000109] __x64_sys_ioctl+0x11/0x20 [ +0.000109] do_syscall_64+0x3e/0x70 [ +0.000120] entry_SYSCALL_64_after_hwframe+0x44/0xa9 [ +0.000112] RIP: 0033:0x7fbe9cdbb67b [ +0.000110] Code: Bad RIP value. [ +0.000124] RSP: 002b:00007ffd61ff5778 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 [ +0.000170] RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 00007fbe9cdbb67b [ +0.000114] RDX: 00007ffd61ff5780 RSI: 00000000c0484e43 RDI: 0000000000000003 [ +0.000113] RBP: 0000000000000000 R08: 0000000000000001 R09: 0000000000000000 [ +0.000115] R10: 0000000000000000 R11: 0000000000000246 R12: 00007ffd61ff7219 [ +0.000123] R13: 0000000000000006 R14: 00007ffd61ff5e30 R15: 000055e09c1854a0 [ +0.000115] Kernel panic - not syncing: hung_task: blocked tasks You could easily reproduce this by running below, parallelly, for 10min: while [ 1 ]; do nvme write-zeroes /dev/nvme0n1 -s 1 -c 1; done while [ 1 ]; do echo 1 > /sys/block/nvme0n1/device/reset_controller; done while [ 1 ]; do ifconfig enp2s0f4 down; sleep 24; ifconfig enp2s0f4 up; sleep 28; done Not sure using nvme-write this way is valid or not.. Thanks, Krishna. On Tuesday, July 07/28/20, 2020 at 08:54:18 -0700, Sagi Grimberg wrote: > > > On 7/28/20 4:59 AM, Krishnamraju Eraparaju wrote: > >Sagi, > >With the given patch, I am no more seeing the freeze_queue_wait hang > >issue, but I am seeing another hang issue: > > The trace suggest that you are not running with multipath right? > > I think you need the patch: > [PATCH] nvme-fabrics: allow to queue requests for live queues > > You can find it in linux-nvme
